package com.info33.platform.business.app.util.excel;

import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;

import java.io.OutputStream;
import java.util.List;

public class ExportExcelUtil {

    private List<Excel> excels;

    // 构造函数，传入要导出的数据
    public ExportExcelUtil(List<Excel> excels) {
        this.excels = excels;
    }

    // 导出数据
    public void export(OutputStream out) throws Exception {
        try {
            HSSFWorkbook workbook = new HSSFWorkbook();
            for (Excel excel:excels){
                String title = excel.getTitle();
                String[] rowName = excel.getRowName();
                List<Object[]> dataList = excel.getDataList();
                HSSFSheet sheet = workbook.createSheet(title);
                // 产生表格标题行
                HSSFRow rowm = sheet.createRow(0);
                HSSFCell cellTitle = rowm.createCell(0);
                //sheet样式定义【】
                HSSFCellStyle columnTopStyle = this.getColumnTopStyle(workbook);
                HSSFCellStyle style = this.getStyle(workbook);
                sheet.addMergedRegion(new CellRangeAddress(0, 1, 0, (rowName.length - 1)));
                cellTitle.setCellStyle(columnTopStyle);
                cellTitle.setCellValue(title);
                // 定义所需列数
                int columnNum = rowName.length;
                HSSFRow rowRowName = sheet.createRow(2);
                // 将列头设置到sheet的单元格中
                for (int n = 0; n < columnNum; n++) {
                    HSSFCell cellRowName = rowRowName.createCell(n);
                    cellRowName.setCellType(CellType.STRING);
                    HSSFRichTextString text = new HSSFRichTextString(rowName[n]);
                    cellRowName.setCellValue(text);
                    cellRowName.setCellStyle(columnTopStyle);
                }
                // 将查询到的数据设置到sheet对应的单元格中
                for (int i = 0; i < dataList.size(); i++) {
                    Object[] obj = dataList.get(i);// 遍历每个对象
                    HSSFRow row = sheet.createRow(i + 3);// 创建所需的行数
                    for (int j = 0; j < obj.length; j++) {
                        HSSFCell cell = null;
                        if (j == 0) {
                            cell = row.createCell(j, CellType.NUMERIC);
                            cell.setCellValue(i + 1);
                        } else {
                            cell = row.createCell(j, CellType.STRING);
                            if (!"".equals(obj[j]) && obj[j] != null) {
                                cell.setCellValue(obj[j].toString());
                            }else {
                                cell.setCellValue("");
                            }
                        }
                        cell.setCellStyle(style);
                    }
                }
                // 让列宽随着导出的列长自动适应
                for (int colNum = 0; colNum < columnNum; colNum++) {
                    int columnWidth = sheet.getColumnWidth(colNum) / 256;
                    for (int rowNum = 0; rowNum < sheet.getLastRowNum(); rowNum++) {
                        HSSFRow currentRow;
                        if (sheet.getRow(rowNum) == null) {
                            currentRow = sheet.createRow(rowNum);
                        } else {
                            currentRow = sheet.getRow(rowNum);
                        }
                        if (currentRow.getCell(colNum) != null) {
                            HSSFCell currentCell = currentRow.getCell(colNum);
                            if (currentCell.getCellTypeEnum () == CellType.STRING) {
                                int length = currentCell.getStringCellValue().getBytes("GBK").length;
                                if (columnWidth < length) {
                                    columnWidth = length;
                                }
                            }
                        }
                    }
                    //列宽最大值65000,超过则报错:The maximum column width for an individual cell is 255 characters.
                    //可设置为15000
                    if (colNum == 0) {
                        sheet.setColumnWidth(colNum, (columnWidth - 2) * 256);
                    } else {
                        int i = columnWidth * 300;
                        if(i > 15000){
                            i = 15000;
                        }
                        sheet.setColumnWidth(colNum, i);
                    }
                }
            }
            workbook.write(out);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /*
   * 列头单元格样式
   */
    public HSSFCellStyle getColumnTopStyle(HSSFWorkbook workbook) {
        // 设置字体
        HSSFFont font = workbook.createFont();
        // 设置字体大小
        font.setFontHeightInPoints((short) 11);
        // 字体加粗
        font.setBold(true);
        // 设置字体名字
        font.setFontName("Courier New");
        // 设置样式
        HSSFCellStyle style = workbook.createCellStyle();
        // 设置低边框
        style.setBorderBottom(BorderStyle.THIN);
        // 设置低边框颜色
        style.setBottomBorderColor(IndexedColors.BLACK.index);
        // 设置右边框
        style.setBorderRight(BorderStyle.THIN);
        // 设置顶边框
        style.setTopBorderColor(IndexedColors.BLACK.index);
        // 设置顶边框颜色
        style.setTopBorderColor(IndexedColors.BLACK.index);
        // 在样式中应用设置的字体
        style.setFont(font);
        // 设置自动换行
        style.setWrapText(false);
        // 设置水平对齐的样式为居中对齐；
        style.setAlignment(HorizontalAlignment.CENTER);
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        return style;
    }

    public HSSFCellStyle getStyle(HSSFWorkbook workbook) {
        // 设置字体
        HSSFFont font = workbook.createFont();
        // 设置字体大小
        font.setFontHeightInPoints((short) 10);
        // 字体加粗
        font.setBold(true);
        // 设置字体名字
        font.setFontName("Courier New");
        // 设置样式;
        HSSFCellStyle style = workbook.createCellStyle();
        // 设置底边框;
        style.setBorderBottom(BorderStyle.THIN);
        // 设置底边框颜色;
        style.setBottomBorderColor(IndexedColors.BLACK.index);
        // 设置左边框;
        style.setBorderLeft(BorderStyle.THIN);
        // 设置左边框颜色;
        style.setLeftBorderColor(IndexedColors.BLACK.index);
        // 设置右边框;
        style.setBorderRight(BorderStyle.THIN);
        // 设置右边框颜色;
        style.setRightBorderColor(IndexedColors.BLACK.index);
        // 设置顶边框;
        style.setBorderTop(BorderStyle.THIN);
        // 设置顶边框颜色;
        style.setTopBorderColor(IndexedColors.BLACK.index);
        // 在样式用应用设置的字体;
        style.setFont(font);
        // 设置自动换行;
        style.setWrapText(false);
        // 设置水平对齐的样式为居中对齐;
        style.setAlignment(HorizontalAlignment.CENTER);
        // 设置垂直对齐的样式为居中对齐;
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        return style;
    }
}
